The invention relates generally to railway car coupling systems, and more particularly to an improved cast metal coupler-knuckle assembly.
This invention is applicable to Association of American Railroads (AAR) Type E, F, and H couplers. In a standard railway coupler-knuckle assembly, a knuckle pin pivotally connects a coupler body and a knuckle. Both the coupler body and the knuckle have a pinhole that allows a single knuckle pin to pivotally secure the coupler and the knuckle together.
In the coupler-knuckle assembly design that is currently used in the railway industry, the knuckle's weakest section is in the throat area around the hole for the knuckle pin. The hole is 1 21/32 inches in diameter and goes completely through the coupler and the knuckle. The pinhole reduces the cross-section area of the knuckle's throat area, which is a highly stressed location in the coupler-knuckle assembly. Because of this weakness in the throat area of the knuckle, the current AAR cast metal coupler-knuckle assembly design does not consistently meet the AAR's newly adopted M-216 fatigue test for a coupler-knuckle assembly.
The current single style knuckle pin designs are either metallic or non-metallic. When in use, the knuckle pin can get loaded due to the misalignment of the pulling lugs and pinholes located both on the coupler body and the knuckle. The misalignment causes both the knuckle pin and the coupler-knuckle assembly to fatigue during use, and can cause damage or break the pin or assembly.
The present invention provides an improved railway coupler-knuckle assembly that strengthens the coupler-knuckle assembly and reduces fatigue on all components of the coupler-knuckle assembly.